A Path Computation Element (PCE) is an entity that is capable of computing a network path or route based on a network topology, and applying computational constraints to the computation. The capability of a PCE to compute different types of paths allows a PCE to provide traffic engineering functions.
A PCE-based network architecture defines PCEs to perform computation of a multi-layer path, and take constraints into consideration. A multi-layer network may be considered as distinct path computation regions within a PCE domain, and therefore, a PCE-based architecture is useful to allow path computation from one layer network region, across the multi-layer network, to another layer network region. A PCE may be placed on a single network node with high processing capabilities, or several PCEs might be deployed on nodes across a network.
A large-scale path computation need may arise when network operators need to set up a large number of Traffic Engineering Label Switched Paths (TE-LSPs) in a network planning process. Hence, a large-scale path computation is typically an off-line computation.
The off-line computation requirements to support a large number of TE-LSPs are quite different from on-line path computation requirements. While on-line path computation is focused on finding the best path given network conditions in timely manner, a large-scale off-line path computation application involves finding a large number of TE-LSPs that concurrently meet a global objective.
While off-line computation may not require as stringent time constraint as on-line path computation, the key objective associated with large-scale off-line computation is to efficiently allocate network resources from a global network perspective. While on-line path computation is tactical, off-line large-scale path computation is strategic.
As a Path Computation Element (PCE) is considered to provide solutions in path computation in a communication network, a PCE may provide solutions for large-scale off-line concurrent path computation needs.
Therefore, there is a need for a system that provides efficient and feasible capability enabling a PCE to perform a global concurrent path computation.